Refocusing refers to reselecting a focal plane or a depth-of-field of a picture according to a user need after the picture is formed. When watching the picture, a viewer may select a scenery of interest to make the scenery clear, without having to passively watch a themed scenery selected by a photographer.
According to a refocusing method in the prior art, refocusing can be performed only on a single depth plane. In this manner, only one area corresponding to one depth plane can be selected at a time. However, in an actual application, a user may need to perform refocusing on multiple depth planes or one or more depth intervals, and the existing refocusing method cannot meet the user need. Even adding buttons or setting a multi-level menu cannot well resolve this problem, only to add memory load of the user. Therefore, a multi-depth-interval refocusing method urgently needs to be proposed.